tests: Add mypy to the tests
This also moves things to pre-commit similar to other projects.
Also fixes some type issues that mypy found around.
Signed-off-by: David Caro dcaro@wikimedia.org
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This also moves things to pre-commit similar to other projects.
Also fixes some type issues that mypy found around.
Signed-off-by: David Caro dcaro@wikimedia.org